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A classic result in antiderivative theory
A classic result in antiderivative theory
Source:
November 28, 2019
function
calculus
real analysis
primitives
Problem Statement
Let be a function
f
:
R
⟶
R
≥
0
f:\mathbb{R}\longrightarrow\mathbb{R}_{\ge 0}
f
:
R
⟶
R
≥
0
that admits primitives and such that
lim
x
→
0
f
(
x
)
x
=
0.
\lim_{x\to 0 } \frac{f(x)}{x} =0.
lim
x
→
0
x
f
(
x
)
=
0.
Prove that the function
g
:
R
⟶
R
,
g:\mathbb{R}\longrightarrow\mathbb{R} ,
g
:
R
⟶
R
,
defined as
g
(
x
)
=
{
f
(
x
)
/
x
,
e
m
s
p
;
x
≠
0
0
,
e
m
s
p
;
x
=
0
,
g(x)=\left\{ \begin{matrix} f(x)/x ,&  x\neq 0\\ 0,&   x=0 \end{matrix} \right. ,
g
(
x
)
=
{
f
(
x
)
/
x
,
0
,
e
m
s
p
;
x
=
0
e
m
s
p
;
x
=
0
,
is primitivable.
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